The Contiki operating system allows tiny wireless battery-operated devices to communicate using IPv6 - a concept known as the Internet of Things. The Contiki team has just released Contiki 2.5, which brings ContikiRPL, the new default low-power IPv6 routing protocol, and ContikiMAC, which allows nodes to keep their radios off more than 99% of the time yet communicate with each other using wireless multi-hop networking. The Contiki Wiki has more information on Contiki.